I think you should call Monroe Tech Support and ask them. A steering stabilizer that can't be mounted sideways isn't much good! Call Monroe at (734) 384-7809, 8:30 a.m. - 5:30 p.m. EST
Here is what Monroe has to say about mounting shocks upside down (from their website FAQ):
Q: Can shock absorbers be mounted upside down (rod end down) and still function properly?
A. Most modern shock absorbers utilize a twin (dual) tube construction; in order to work properly the inner of the two tubes (working chamber) should stay completely filled with oil. The outer (reserve) tube contains an oil reserve along with air or a pressurized gas. If the unit is mounted inverted (rod side down), the air or gas in the outer chamber can enter the inner working chamber, resulting in poor damping performance. Therefore, twin tube shock absorbers should not be mounted upside down (or on their side), with the exception of specially designed units that incorporate a gas cell, or cellular gas material, designed to keep the gas retained in the outer reserve tube.
2004 American Tradition; 2014 Buick LaCRosse
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